make test support for dynamic backend module (ITS#2401)

[taru@debian.org]

Full_Name: Masato Taruishi
Version: CVS HEAD
OS: Linux
URL: ftp://ftp.openldap.org/incoming/Masato-Taruishi-030326.patch
Submission from: (NULL) (210.128.90.14)


Currently, OpenLDAP skips make test for dynamic backend modules.
Because I build all backends as dynamic modules, I'd like to test these
backends too. This trival patch supports make test for dynamic backends.
These are the summaries of tha patch:

   * propagates BACKENDTYPE to all test scripts.
   * adds modulepath ../servers/slapd/back-@BACKEND@ to all slapd-*.conf
   * adds the @MODULELOAD@ variable to all slapd-*.conf and conf.sh
     extracts it to moduleload back_@BACKEND@.la only when the BACKENDTYPE
     is mod.
   * moves argument handling codes of test scripts to scripts/args.sh
      (Basically, this is not a necessary modification. )

Thanks in advance